MBlazeAsmPrinter.cpp revision 6e749f31c6373b31b780ce29d2900f965f42a2f0 
1//===-- MBlazeAsmPrinter.cpp - MBlaze LLVM assembly writer ----------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file contains a printer that converts from our internal representation
11// of machine-dependent LLVM code to GAS-format MBlaze assembly language.
12//
13//===----------------------------------------------------------------------===//
14
15#define DEBUG_TYPE "mblaze-asm-printer"
16
17#include "MBlaze.h"
18#include "MBlazeSubtarget.h"
19#include "MBlazeInstrInfo.h"
20#include "MBlazeTargetMachine.h"
21#include "MBlazeMachineFunction.h"
22#include "MBlazeMCInstLower.h"
23#include "InstPrinter/MBlazeInstPrinter.h"
24#include "llvm/Constants.h"
25#include "llvm/DerivedTypes.h"
26#include "llvm/Module.h"
27#include "llvm/CodeGen/AsmPrinter.h"
28#include "llvm/CodeGen/MachineFunctionPass.h"
29#include "llvm/CodeGen/MachineConstantPool.h"
30#include "llvm/CodeGen/MachineFrameInfo.h"
31#include "llvm/CodeGen/MachineInstr.h"
32#include "llvm/MC/MCInst.h"
33#include "llvm/MC/MCStreamer.h"
34#include "llvm/MC/MCAsmInfo.h"
35#include "llvm/MC/MCSymbol.h"
36#include "llvm/Target/Mangler.h"
37#include "llvm/Target/TargetData.h"
38#include "llvm/Target/TargetLoweringObjectFile.h"
39#include "llvm/Target/TargetMachine.h"
40#include "llvm/Target/TargetOptions.h"
41#include "llvm/Target/TargetRegistry.h"
42#include "llvm/ADT/SmallString.h"
43#include "llvm/ADT/StringExtras.h"
44#include "llvm/Support/ErrorHandling.h"
45#include "llvm/Support/raw_ostream.h"
46#include <cctype>
47
48using namespace llvm;
49
50namespace {
51  class MBlazeAsmPrinter : public AsmPrinter {
52    const MBlazeSubtarget *Subtarget;
53  public:
54    explicit MBlazeAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
55      : AsmPrinter(TM, Streamer) {
56      Subtarget = &TM.getSubtarget<MBlazeSubtarget>();
57    }
58
59    virtual const char *getPassName() const {
60      return "MBlaze Assembly Printer";
61    }
62
63    bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
64                         unsigned AsmVariant, const char *ExtraCode,
65                         raw_ostream &O);
66    void printOperand(const MachineInstr *MI, int opNum, raw_ostream &O);
67    void printUnsignedImm(const MachineInstr *MI, int opNum, raw_ostream &O);
68    void printFSLImm(const MachineInstr *MI, int opNum, raw_ostream &O);
69    void printMemOperand(const MachineInstr *MI, int opNum, raw_ostream &O,
70                         const char *Modifier = 0);
71
72    void EmitInstruction(const MachineInstr *MI);
73  };
74} // end of anonymous namespace
75
76// #include "MBlazeGenAsmWriter.inc"
77
78//===----------------------------------------------------------------------===//
79//
80//  MBlaze Asm Directives
81//
82//  -- Frame directive "frame Stackpointer, Stacksize, RARegister"
83//  Describe the stack frame.
84//
85//  -- Mask directives "mask  bitmask, offset"
86//  Tells the assembler which registers are saved and where.
87//  bitmask - contain a little endian bitset indicating which registers are
88//            saved on function prologue (e.g. with a 0x80000000 mask, the
89//            assembler knows the register 31 (RA) is saved at prologue.
90//  offset  - the position before stack pointer subtraction indicating where
91//            the first saved register on prologue is located. (e.g. with a
92//
93//  Consider the following function prologue:
94//
95//    .frame  R19,48,R15
96//    .mask   0xc0000000,-8
97//       addiu R1, R1, -48
98//       sw R15, 40(R1)
99//       sw R19, 36(R1)
100//
101//    With a 0xc0000000 mask, the assembler knows the register 15 (R15) and
102//    19 (R19) are saved at prologue. As the save order on prologue is from
103//    left to right, R15 is saved first. A -8 offset means that after the
104//    stack pointer subtration, the first register in the mask (R15) will be
105//    saved at address 48-8=40.
106//
107//===----------------------------------------------------------------------===//
108
109//===----------------------------------------------------------------------===//
110void MBlazeAsmPrinter::EmitInstruction(const MachineInstr *MI) {
111  MBlazeMCInstLower MCInstLowering(OutContext, *Mang, *this);
112
113  MCInst TmpInst;
114  MCInstLowering.Lower(MI, TmpInst);
115  OutStreamer.EmitInstruction(TmpInst);
116}
117
118// Print a 32 bit hex number with all numbers.
119static void printHex32(unsigned int Value, raw_ostream &O) {
120  O << "0x";
121  for (int i = 7; i >= 0; i--)
122    O << utohexstr((Value & (0xF << (i*4))) >> (i*4));
123}
124
125
126// Print out an operand for an inline asm expression.
127bool MBlazeAsmPrinter::
128PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
129                unsigned AsmVariant,const char *ExtraCode, raw_ostream &O) {
130  // Does this asm operand have a single letter operand modifier?
131  if (ExtraCode && ExtraCode[0])
132    return true; // Unknown modifier.
133
134  printOperand(MI, OpNo, O);
135  return false;
136}
137
138void MBlazeAsmPrinter::printOperand(const MachineInstr *MI, int opNum,
139                                    raw_ostream &O) {
140  const MachineOperand &MO = MI->getOperand(opNum);
141
142  switch (MO.getType()) {
143  case MachineOperand::MO_Register:
144    O << MBlazeInstPrinter::getRegisterName(MO.getReg());
145    break;
146
147  case MachineOperand::MO_Immediate:
148    O << (int32_t)MO.getImm();
149    break;
150
151  case MachineOperand::MO_FPImmediate: {
152    const ConstantFP *fp = MO.getFPImm();
153    printHex32(fp->getValueAPF().bitcastToAPInt().getZExtValue(), O);
154    O << ";\t# immediate = " << *fp;
155    break;
156  }
157
158  case MachineOperand::MO_MachineBasicBlock:
159    O << *MO.getMBB()->getSymbol();
160    return;
161
162  case MachineOperand::MO_GlobalAddress:
163    O << *Mang->getSymbol(MO.getGlobal());
164    break;
165
166  case MachineOperand::MO_ExternalSymbol:
167    O << *GetExternalSymbolSymbol(MO.getSymbolName());
168    break;
169
170  case MachineOperand::MO_JumpTableIndex:
171    O << MAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
172      << '_' << MO.getIndex();
173    break;
174
175  case MachineOperand::MO_ConstantPoolIndex:
176    O << MAI->getPrivateGlobalPrefix() << "CPI"
177      << getFunctionNumber() << "_" << MO.getIndex();
178    if (MO.getOffset())
179      O << "+" << MO.getOffset();
180    break;
181
182  default:
183    llvm_unreachable("<unknown operand type>");
184  }
185}
186
187void MBlazeAsmPrinter::printUnsignedImm(const MachineInstr *MI, int opNum,
188                                        raw_ostream &O) {
189  const MachineOperand &MO = MI->getOperand(opNum);
190  if (MO.isImm())
191    O << (uint32_t)MO.getImm();
192  else
193    printOperand(MI, opNum, O);
194}
195
196void MBlazeAsmPrinter::printFSLImm(const MachineInstr *MI, int opNum,
197                                   raw_ostream &O) {
198  const MachineOperand &MO = MI->getOperand(opNum);
199  if (MO.isImm())
200    O << "rfsl" << (unsigned int)MO.getImm();
201  else
202    printOperand(MI, opNum, O);
203}
204
205void MBlazeAsmPrinter::
206printMemOperand(const MachineInstr *MI, int opNum, raw_ostream &O,
207                const char *Modifier) {
208  printOperand(MI, opNum, O);
209  O << ", ";
210  printOperand(MI, opNum+1, O);
211}
212
213static MCInstPrinter *createMBlazeMCInstPrinter(const Target &T,
214                                                unsigned SyntaxVariant,
215                                                const MCAsmInfo &MAI) {
216  if (SyntaxVariant == 0)
217    return new MBlazeInstPrinter(MAI);
218  return 0;
219}
220
221// Force static initialization.
222extern "C" void LLVMInitializeMBlazeAsmPrinter() {
223  RegisterAsmPrinter<MBlazeAsmPrinter> X(TheMBlazeTarget);
224  TargetRegistry::RegisterMCInstPrinter(TheMBlazeTarget,
225                                        createMBlazeMCInstPrinter);
226
227}
228